docs: def pubkey(self, identity, ecdh=False):
          """Return public key."""
          curve_name = identity.get_curve_name(ecdh=ecdh)
          log.debug('"%s" getting public key (%s) from %s',
                    identity.to_string(), curve_name, self)
          addr = identity.get_bip32_address(ecdh=ecdh)
          result = self._defs.get_public_node(
              self.conn,
              n=addr,
              ecdsa_curve_name=curve_name)
          log.debug('result: %s', result)
          return bytes(result.node.public_key)